Self ventilating roof system

ABSTRACT

A self-ventilating roofing system that consists of a rigid deck that is connected to the roof support system and has a horizontal opening parallel to the eave, on both slopes, but above the attic space. There is also an opening on either side of the ridge. A radiant barrier comprising of a reflective coating is applied over the roof deck. A slice is made over the lower and upper opening of the deck to allow air to enter the lower opening and exit the upper opening. A panel with vertical grooves is installed over the radiant barrier with the groove side face down. This panel is made of a type of insulated material. A metal drip edge is then installed along the eave. This drip edge should be installed with an air gap between the facia and the drip edge sufficiently wide enough to allow air to enter. A vented ridge vent is then installed at the ridge to allow for the weather proof exit of the air. If a metal roof is being installed then the metal panels can be attached on top of the insulated panel. If an asphalt shingle or wood shake roof is being installed then a nailable panel must be installed over the insulated panel.

TECHNICAL FIELD

This invention can be applied to any roof structure, existing or new,with the result being to slow or stop radiant, convective, and directheat from entering the roofing structure as well as the area directlybelow the roofing structure. This becomes an automatic non mechanicaltechnique that works using three laws of nature, the radiant heattheory, the law of convective heat transfer and the law of hot airrising (2^(nd) law of thermodynamics). This invention also exhaustshumid moist air and creates a thermal break, while creating anenvironment where ventilation occurs naturally in the roof system andbelow the roof system or attic space.

BACKGROUND OF THE INVENTION

Historically speaking, the purpose of most roofing structures was tokeep the structure they covered dry. That is to keep out rain, snow andwind. Originally these structures were very drafty and no thought wasgiven to ventilating the attic or roofing structures. The challenge hasbecome how to introduce an efficient but economic system for olderstructures and for new structures. Many of the older buildings werebuilt without any eave overhangs or soffit. This prevents the standardmethod of introducing circulating air through a soffit vent into theseolder structures.

In the inventions that use ventilation to stop convective heat and athermal break to stop direct heat none of these inventions add radianttechnology to stop radiant heat. This added step addresses all threeways heat is absorbed into a roofing system.

Anthony J. Crookston, U.S. Pat. No. 5,473,847 A utilized the ventilationaspect as well as the thermal break aspect but not the radiant barrieraspect. This invention also did not allow air to enter the roofingstructure under the lower eave/drip edge which meant that snow and/orice could block this vent and keep air ventilation from occurring in thewinter.

Atlas Roofing Corporation also has a similar roofing ventilation productas Mr. Crookston. This product does not use radiant barrier technologyas well.

RePack (http://www.atlasroofing.com/news.php?section_url=147&news_id=15)also has similar products using a type of rigid insulation but without aradiant barrier.

ORNL roof-and-attic system(http://www.gizmag.com/ornl-roof-and-attic-system/24083/) does useradiant technology but only to vent the existing hot air from the attic.Their system does not introduce new “cooler” air into the attic butexhausts the attic of existing hot air after the attic is sealed.

In conclusion, this invention is not only unique but more effective dueto the radiant technology that is included.

SUMMARY OF THE INVENTION

This invention introduces a system whereby air can be introduced underthe eave drip edge and channeled into the attic, or air space under theroofing system as well as under the roofing membrane. This creates aircirculation and ventilation which slows or stops the convective heattransfer into the structure. Since hot air always rises this process isautomatic. The air exits the attic space as well as the roofing systemthrough a vented ridge cap that runs the entire length of the ridge orhip in cases of a hip roof.

This invention addresses the three ways heat is transferred into astructure: direct heat transfer, think of a tea kettle on an open flame,convective heat transfer, think of the hot air in an oven cooking aturkey, and radiant heat transfer, think of popcorn in a microwave.

Direct heat transfer is slowed or stopped by using an insulated panel asa thermal break. This insulated panel is installed over the entire roofdeck and due to its insulating qualities it prevents heat from beingtransferred from the roof surface into the structure.

Convective heat is slowed or stopped by implementing moving air toremove the convective heat. This is done by cutting in vertical groovesin the underside of the insulated panel to enable the air to move alongthese channels. As the roof surface heats the air the hot air will riseand exit through a vented ridge cap installed along the ridge.

Radiant heat transfer is stopped or slowed by installing a reflectivemembrane on the surface of the deck. Since a radiant barrier will onlywork if there is an air gap the grooves in the underside of theinsulated panel are used in conjunction with the radiant barrier tocreate this air gap. The radiant heat from the sun is then reflectedaway from the roof structure using this method.

The Self Ventilation Roof system will utilize the three heat transferblocking methods as well as ventilate air in the attic or space belowthe roof system. This is accomplished by creating an air gap under theeave drip edge so air can enter into the roof system. A small slice ofthe roof deck, above the attic space, is created and air then will enterthe attic space and exit the vented ridge cap at the apex of the roofstructure. In this way both the attic space and roof system utilizes thelaw of hot air rising to ventilate both the attic and roof system.

These three methods are employed by this invention to offer an effectiveand economical way to enhance the energy efficiency of old and newstructures.

To stop the radiant transfer of heat into the structure in the summerand out of the structure in the winter, a reflective water proof butvapor permeable membrane is installed over the roof deck. This servesthe dual purpose of a radiant barrier as well as a waterproof membraneto dry in the structure during construction. For a radiant barrier towork there needs to be an air gap on at least one side. This reflectivemembrane is perforated to allow water vapor to flow through the membranebut not to allow water to penetrate the reflective membrane.

To stop or slow the direct heat transfer in the summer and the directcold transfer in the winter a vertically grooved insulated panel isinstalled over the reflective membrane. If the reflective membrane isinstalled first the grooves are placed adjacent to the reflectivemembrane. If the panels are installed first then the grooves will faceupward or away from the roof deck and the reflective membrane isinstalled on top of the grooves. This insulated panel acts as a thermalbreak for the entire roof system and stops or slows the direct transferof heat or cold.

To stop the convective transfer of heat in the summer air ventilation isintroduced through the air grooves in the insulated panel. Where moreventilation is needed the panels can be installed with both sidesvertically grooved and the reflective membrane can be installed on thedeck side of the panel or upper side. This system allows air to beheated under the roof system by the heat of sun on the roof surfacebeing transferred to the air in the air grooves of the insulated andgrooved panel. As the air heats it rises and exits out the vented ridgecap. As hot air exits the vented ridge cap cooler air is drawn in underthe eave drip edge and is channeled vertically up the grooves in theinsulated panel.

To ventilate the attic space more effectively a horizontal cut in theroof deck is made about 1 to 2 feet above where the vertical outsidesupport wall intersects the roof structure. In this way the air thatflows up the insulated panel will also enter the attic and helpventilate the attic space by exiting through a parallel space introducedat the ridge of the roof. As hot air exits through the vented ridge ventmore cool air is pulled in behind the offset eave drip edge and throughexisting soffit vents if any.

This entire roof system can be used on any pitch of roof and can acceptany profile or type of roofing material.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 shows a cut away view of a roofing system (in this illustration agable roof) with the reflective barrier, venting insulation panel andthe entry air flow direction.

FIG. 2 shows a cut away side view of this invention from eave to ridgewith a close up view of the ridge venting system for this invention.

FIG. 3 shows a close up side view of the eave drip edge area and how theair enters through the flow through vent and into the grooved andinsulated panel.

FIG. 4 shows a cut away view of a roofing system (in this illustration agable roof) with the refective barrier, double grooved ventinginsulation panel and the entry airflow direction.

DETAILED DESCRIPTION FIG. 1

FIG. 1 This invention is meant for use on either flat or pitched roofs.In FIG. 1 the example used to illustrate this invention is a slopedgable roof with asphalt shingles as the exterior roofing surface. Anyprofile of roofing material can be used. From bottom to top #10 is thegutter system that may or may not be used as this is just forillustration, the gutter system is not a part of the invention. Ifdesired it is attached to and through the metal drip edge preferably butnot exclusively with a hidden hanger system common to gutter systems.#20 is an eave drip edge commonly made of a type of metal or aluminum.It extends above the flow through vent #70 and is attached by fastenersthrough the flow through vent #70 into the deck #50 of the roofstructure.

#90 is the air flow direction and enters the invention through the gapbetween the eave drip edge and the fascia #40. Then the air #90 passesthrough the #60 insect and bug screen, keeping insects out of theroofing system. The air #90 then continues through the flow through vent#70 comprised of panels with air channels, sandwiched on top of eachother in a way that air flows freely through the flow through vent.After the air #90 passes through the flow through vent #70 it continuesin an upward direction passing over the #80 reflective barrier. This #80reflective barrier is perforated with holes throughout its surface sothat vapor can pass through it but water molecules cannot penetrate it.In this way it can also act as a waterproofing membrane duringconstruction but still allows any condensation that occurs between the#80 reflective barrier and the roof structure decking #50 to flowthrough these penetrations and evaporate as the #30 air flows over it onits journey through the #100 vented and insulated panel. This reflectivemembrane #80 is made of a type of material that has a reflective ratingof over 95% so that it will act as a radiant barrier and thus reflect amajority of the reflective or radiant heat that is caused by the sun'srays. This reflective barrier #80 or radiant barrier shall be bonded toa strong center fabric thus providing a strong membrane to walk on andless likely to tear and be a safety concern. This reflective membrane#80 must be adjacent to an air gap such as the #100 panel contains orits ability to reflect the radiant heat away from the structure will begreatly compromised. In some cases the #100 panel also can be installeddirectly on the roof deck with the grooves facing up and then the #80reflective membrane can be installed over the grooves in the panel.

Reflective barrier or Radiant barrier #80 that provides a means by whichradiant heat waves are reflected away from the roof and attic structureto cause cooler temperatures thus reducing the energy needed to cool thestructure. An air gap is needed for the radiant reflection to work andis present using air channels adjacent to the radiant barrier on theunderside of the thermal break.

The reflective barrier or radiant barrier #80 is vapor permeable toallow water vapor or condensation to permeate the membrane and then bedried by the ventilated air in the ventilation system.

The reflective barrier or radiant barrier #80 is water proof and doesnot allow water molecules to penetrate it thus adding another componentto waterproof the roof structure or dry in the roof structure duringconstruction.

The reflective barrier or radiant barrier #80 is double sided and has atleast a 95% reflectivity that will radiate away from the structureduring the hot months of the year.

The reflective barrier or radiant barrier #80 shall be bonded to astrong center fabric thus providing a strong membrane to walk on andless likely to tear and be a safety concern.

The reflective barrier or radiant barrier #80 makes this inventionunique in that while there are various ventilation systems in existencewe could not find any that incorporated radiant barrier technology.

These #100 panels are made of a type of insulated material that acts asa thermal break so as to slow or stop the transfer of cold or heatdepending on the outside temperature.

Thermal break #100 that provides a means by which an insulated panel isinstalled adjacent to the radiant barrier and insulates the roof frompassing the hot or cold temperature on the membrane of the roofingsystem into the roof structure.

The thermal break #100 stops or greatly reduces thermal bridging overentire roof structure. Thermal bridging occurs when any part of aroofing structure is not insulated from direct contact with any part ofthe roofing structure that comes into direct contact with the outsideambient air.

The thermal break #100 allows for a medium to locate vertical airchannels to allow the radiant barrier the air gap it needs to beeffective and the air pathways for ventilating hot air out of the roofstructure.

The thermal break #100 also adds R value insulation depending on itsdensity and thickness.

These #100 panels have grooves running from top to bottom throughout the#100 panel allowing air to flow along these grooves #90 from the entryat the eave to exit near the ridge. This air flow #90 will remove thehot air #90 that the radiant heat of the sun has caused because of thelaw that hot air rises and as it exits the invention at the ridgecausing cooler air to be drawn in through the eave drip edge system #20eave drip edge, #40 fascia, #60 insect and bug screen & #70 flow throughvent making this process continuous and constant.

In this particular illustration there is a solid deck #50 common to theentire roof structure as is common in residential construction. To allowthe attic space to ventilate better a slice is #140 is introduced intothe solid deck #50. This lets air into the space below the deckventilate. As air enters through thw #140 slice in the #50 deck it exitsout of the ridge vent at the apex of the roofing structure. This coolsor ventilates the attic air space. In commercial construction or olderexisting buildings a solid roof deck may not be present, instead a woodor metal purloin system or skip sheathing or some similar deck may be inplace. This invention will work with any type of roofing deck.

After the slice #140 has been cut into the roof deck #50 and after thereflective membrane #80 has been installed over the entire roof deck anda slice has been removed from the refective membrane #80 over the airgap #140 so air #90 can freely enter the attic space and the insulatedand grooved panels have been installed over the entire roof deck in sucha way as the grooves run continuously from bottom to top allowing air#90 to freely flow to the ridge vent assembly at the ridge of the roofthen another deck of material #110 is installed to provide the requirednailable surface to fasten the chosen roofing material to the roof deck#110 whether it be wood or some other approved material. After theapproved deck #110 has been installed then a water proof membrane #120can be installed according to the manufacturer's instructions. Lastly aroofing membrane #130 can be installed as per the manufacturer'sinstructions. Any roofing material #130 can be installed on thisinvention without compromising its integrity or its ability to work asintended. The roofing surfaces that can be installed on this nailablesurface can be asphalt shingles, wood shakes, any profile of metalroofs, clay or concrete tile but are limited to these roofs.

A Convective air ventilation system that provides a means by which thehot air is exited through a vented ridge cap and cooler air is drawn infrom an eave venting system. This hot air is carried away from the roofsystem via the air channels used to make the radiant barrier operable.The cool air that is drawn in through the eave venting system alsointroduces cool air into the attic area via the slice #140 in the deck#50. As the hot air escapes through the vented ridge cap more cool airis drawn into the attic and also into the air channels on the undersideof the thermal break insulated panels #100.

The ventilation system provides a means by which an attic under theventilation system can be cooled, for example in one attic the airtemperature at the apex of the attic measured 150 degrees Fahrenheitprior to the ventilation systems installation. The outside ambient airtemperature was 95 degrees Fahrenheit. After said air ventilation systemwas installed the attic air temperature in the apex of the attic on asimilar 95 degree day measured 103 degrees Fahrenheit. This particularsystem had a black asphalt shingle roof before and after theinstallation of said air ventilation system.

The ventilation system also provides a means by which the roof membraneor covering can be cooled. This will affect the longevity of most roofcoverings or membranes especially asphalt and fiberglass shingles aswell as wood shake roofs, for example a well-ventilated wood shake roofin arid Colorado can easily experience 2 to 3 times the average life asthat of a non-ventilated roof in the Mid Atlantic. Many asphalt shingleroof warranties are significantly affected if proper ventilation is notincluded.

The ventilation system provides a means by which cooling the attic andthe roof surface lowers the energy used to cool the structure in the hotmonths, for example one house using this system experienced a drop inattic temperature of 50 degrees Fahrenheit and was able to cool afinished room in the attic space from 95 degrees Fahrenheit to 75degrees Fahrenheit using less energy than before the said airventilation system was installed.

The air ventilation system provides a means by which moist humid air canbe vented from the attic of a structure thus lowering the possibility ofmold and mildew occurring.

The air ventilation system may be enhanced by adding solar powered fansin the apex of the roof or under the ridge cap. These fans may bepowered by either a solar panel attached to the roof or attached to theelectrical system of the structure. They may have a timer, or bethermostatically controlled or operate whenever the sun shines. Thisadded ventilation will increase the efficiency of the entire system.

If this system utilizes a structural type thermal break, for example apolyurethane or similar type material that is structural in constructionthen it could become part of the building structure and span aconsiderable distance thus saving on labor and material on rafters andsimilar building components.

FIG. 2

FIG. 2 is a side view of the invention with a blow up or close up of theridge vent area. In FIG. 2 the illustration shows, as in FIG. 1, how theair #90 enters through the gap created at the eave between the drip edge#20 and the fascia #40. This air #90 travels through the bug mesh #60and then through the flow through vent #70 and enters the insulatedpanel #100. In this illustration we are able to see how the air flow #90not only continues upward through the grooved panel #100 but alsothrough a gap in the deck #140. This allows for more air flow in theattic. This additional air #90 introduced into the attic will rise andexit through the ridge vent #150 and cools the attic air temperature aswell as the roof temperature.

In the close up view the illustration depicts the air flow #90 coming upfrom the attic space exiting through the vented ridge vent #150 as wellas the air flow #90 from the grooved insulated panels #100 exiting thevented ridge vent #150.

The vented ridge vent #150 is comprised of a vented or perforated metal,or similar material, J channel that is fastened through to the roofstructure deck #50. In the case of a gable roof there is a mirror imageor process on the adjoining slope. A solid ridge cap #160 is thenattached to the two J channels forming a solid water proof cap along theentire ridge, or in some cases hip.

FIG. 3

FIG. 3 is an illustration of a close up view of the eave area of theinvention. Take special note of how the flow through vent #70 is in theshape of an inverted pyramid. Using this shape assures that if the upperexterior edge of the flow through vent #70 is located directly above theoutside edge of the fascia #40 then there will be an air gap largeenough to allow for sufficient air flow #90 for the invention to work.In some cases an air permeable mesh made of metal or plastic or nylon orsimilar material may take the place of the flow through vent. This meshmaterial must be of sufficient density and strength to not be flattened

As illustrated in this close up a slice #140 is first introduced or cutinto the deck #50 and then the the reflective barrier #80 is installedon the roof deck #50, being careful to remove a corresponding amount ofreflective barrier #80 to allowe air #90 to enter the attic air spaceand then the insulated and grooved panels #100 are installed in thisillustration with the grooves facing the deck #50, and adjacent to thereflective barrier #80. This reflective or radiant barrier #80 shouldhave a 95% reflectivity to be effective. The air flow through theinsulated grooved panels #90 then follows the grooves upward. In thisexample another nailable deck surface #110 is installed on top of thegrooved and insulated panel #100. If, for example, a standing seam metalroof #170 were the chosen roof surface then the additional roof deck#110 would not be needed as the standing seam roof has the ability to beattached by fasteners that would penetrate the entire system through tothe original roof deck #50. If the secondary roof deck #110 is used dueto the need for a nailable surface then a water proof membrane #120 maybe used. The #130 roof material is then applied with the appropriatefasteners.

FIG. 4

FIG. 4 is a view of a double grooved insulated panel #115. A radiantbarrier #80 is installed underneath the double grooved insulated panel#115 as well as on top #105. This allows for air #90 to flow through thelower grooves #90 as well as enter the gap #140 in the deck #50 into theattic space while the air #95 flows through the upper grooves #95 andtravels up the air channels #95 and exits out of the vented ridge ventalong with the air from the lower grooves #90 as well as the air fromthe attic space. This double grooved insulated panel #115 allows forsignificantly more ventilation and air flow and is more effective incooling the roof structure as well as the attic space.

What is claimed is: 1-11. (canceled)
 12. A self ventilating roof systemcomprising: a) a roof structure comprising of: a deck having an uppersurface and a lower surface that covers an open space below said roofstructure, a vented eave located at the lower end of said deck, a ventedridge at the upper end of said deck, and roofing material covering theentire area of said deck from the vented eave to the vented ridge; b) areflective barrier comprising a membrane means that is substantiallyreflective on both sides, waterproof, and allows water vapor to passthrough located on the upper surface of said deck and below said roofingmaterial; c) a thermal break comprising an insulated panel means of a Rvalue greater than 1 with an upper surface and a lower surface with thelower surface adjacent to said reflective barrier and the upper surfaceadjacent the roofing material, said thermal break insulates saidreflective barrier and said roof structure from external heat and cold;said thermal break extends from the vented eave to the vented ridge andincludes means for passing self ventilating air through the selfventilating roof system from the vented eave to the vented ridge betweensaid reflective barrier and the thermal break forming an air gap therebetween and a further ventilation means communicating between said meansfor passing self ventilating air through the self ventilating roofsystem and said open space below said roof structure.
 13. The selfventilating roof system of claim 12, wherein said reflective barrier isat least 95% reflective.
 14. The self ventilating roof system of claim12, wherein said reflective barrier includes perforations throughoutsaid reflective barrier; said perforations are small enough that watermolecules cannot enter through the perforation thus making thereflective barrier waterproof; said perforations, are large enough toallow water vapor to pass through thus allowing any trapped condensationto escape and be dried by the self ventilating air above the reflectivebarrier which reduces or removes the possibility of mold and mildew. 15.The self ventilating roof system of claim 12, wherein said reflectivebarrier has a strong center fabric thus providing a strong membranewhich can be walked on.
 16. The self ventilating roof system of claim12, wherein said reflective barrier sandwiches a durable material thatresists tearing and ripping when attached by standard roofing nailswithout significant pull out.
 17. The self ventilating roof system ofclaim 12, wherein said insulated panel comprises a rigid insulatedmaterial and said means for passing air is air channels in at least thelower surface of said insulated panel; b) said air channels facilitatethe air movement to remove the hot air that has occurred due to theradiant heat exchange from the roofing material to the self ventilatedair thus removing the hot air and bringing in cooler air through theeave, creating a constant and automatic ventilation through thesegrooves as hot air rises; and c) said air channels in the insulatingpanel also dry any condensation that forms and passes through theperforations of the reflective barrier into the air channels and dryingthe condensation to prevent mold and mildew.
 18. The self ventilatingroof system of claim 17, wherein said insulated panel comprises a rigidfoam insulation panel with said air channels formed in the lower surfacethereof.
 19. The self ventilating roof system of claim 17, wherein saidfurther ventilation means connected to said means for passing selfventilating air through the self ventilating roof system and said openspace below said roof structure comprises at least one gap in thecentral area of said deck and said reflective barrier through which airflows between the open space below the deck and said air channels,wherein this additional air introduced into the open space will rise andexit through the vented ridge and cools the air in the open space belowthe deck as well as the roof temperature.
 20. The self ventilating roofsystem of claim 12, wherein said roofing material consisting of one ofthe following: asphalt shingles, wood shakes, metal panels, clay tilesor concrete tiles.
 21. The self ventilating roof system of claim 17,wherein said air channels cover a substantial amount of both upper andlower surfaces of said insulated panel.